《植物生理学报》 2010, 46(3): 241-244

紫萍叶状体衰老过程中的内肽酶谱变化和外源L-丝氨酸对内肽酶谱的影响

刘清岱^1,2, 朱晔荣², 李洪涛², 王勇^2,*

1 天津科技大学食品工程与生物技术学院, 天津300457; 2 南开大学生命科学学院, 天津300071

通信作者：王勇；E-mail: wangyong@nankai.edu.cn；Tel: 022-23504 388

摘　要：

采用双向凝胶电泳技术分析紫萍叶状体衰老期间内肽酶同工酶的变化以及外源L-丝氨酸对内肽酶影响的结果表明, 在衰老的紫萍叶状体中检测到9种内肽酶同工酶, 丝氨酸内肽酶EP3可能在叶状体衰老的早期起作用, 而半胱氨酸内肽酶 EP9 在第 6 天出现, 是衰老后期活性最强的内肽酶。培养液中加入外源的 L- 丝氨酸后, 叶状体蛋白质含量下降加剧, 与衰 老相关的内肽酶 EP3、EP4 和 EP9 的活性明显增强或提前出现。

关键词：紫萍; 叶状体; 衰老; 内肽酶; L-丝氨酸

收稿：2009-11-06   修定：2010-02-10

资助：国家自然科学基金(30870185)。

Changes of Endopeptidase Isoenzymes in Spirodela polyrrhiza Thallus during Senescence and Effect of Exogenous L-Serine on Endopeptidase Isoenzymes

LIU Qing-Dai^{1, 2}, ZHU Ye-Rong², LI Hong-Tao², WANG Yong^2,*

¹College of Food Engineering and Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China; ²College of Life Sciences, Nankai University, Tianjin 300071, China

Corresponding author: WANG Yong; E-mail: wangyong@nankai.edu.cn; Tel: 022-23504 388

Abstract:

Changes in endopeptidase isoenzymes of Spirodela polyrrhiza thallus during senescence and L-serine induced senescence were investigated by two-dimensional electrophoresis. Nine endopeptidases were detected. Changes of these enzymes activities during senescence showed that EP3 (a serine protease) might play a significant role in early stage and the EP9 (a cysteine protease), appeared on the 6th day, was the most active endopeptidase in the late stages of senescence. L-serine treatment of the thallus enhanced the appearance and increase in the activities of three senescence-related endopeptidases (EP3, EP4, EP9), along with its ignificant promotion of decline in protein content.

Key words: Spirodela polyrrhiza; thallus; senescence; endopeptidase; L-serine